This invention relates to an improved trim, cut and form machine containing trimming, cutting and forming modules that produce integrated circuit (IC) packages. The modules contain replaceable trimming, cutting and forming tools and have unique air passages to provide a self-cleaning feature during operation. The modules are inserted into a trimming and forming hydraulic press.
The final steps in the manufacture of an IC chip package such as dual in-line packages (DIP), zig-zag in-line packages (ZIP), plastic leaded chip carriers (PLCC) and small outline J-leaded (SOJ) packages consist of trimming off the excess plastic mold "flash" material that is left behind after plastic encapsulation, trimming off dambar (i.e. metal between leads), cutting the leads to proper length, and forming the leads to a particular configuration. These operations immediately precede the removal of the IC package from its carrier, the lead frame.
Because of the difference in configurations, dimensions and number of leads between IC packages, a large assortment of tools are needed. These trimming, cutting and forming tools are inserted into a trimming and forming hydraulic press.
U.S. Pat. No. 4,079,489 discloses a computer controlled placement machine that punches an IC chip from a film strip, forms the leads and then places the chip on a multi-layer substrate containing a plurality of similar chips.
Prior art trimming and cutting tools have typically been in the shape of a comb. The number of cutting or trimming teeth in the comb would match the number of IC package leads that required cutting or trimming. This number can range typically from 8-30 leads. The consequence of worn or damaged "teeth" in the tool would be that the whole tool would be scrapped. A particular tool can typically process (trim or cut) 50,000-80,000 IC packages prior to replacement for wear.
Additionally, currently available trim and cut machines tend to collect metal and plastic debris such that they remain trapped in the machine. In order to extend the life of the non-lubricated moving machine parts, it is necessary to periodically shut down the machine and perform a cleaning operation to remove metal and plastics particulate.